Refractory furnace lining



Patented'A r. 21, 1925.

UNI-TED STATES PATENT OFFICE.

DANIEL H. MELOCHE, or DETROIT, MICHIGAN, ASSIG-NOR T EARL HoLLE Y, or

nnrnorr, MICHIGAN.

REFRACTORY FURNACE LINING.

No Drawing. Continuation of application Serial No. 581,239, filed August 11, 1922. This application filed April 2, 1923.

To all whom it may concern:

Be it known that I, DANIEL H. Memo rs, a citizen of the United States, residing at 2241 Gladstone Ave, Detroit, in thecounty of Wayne and State of Michigan, have invented certain new and useful Improvements in Refractory Furnace Linings, of which the following is a specification.

This invention relates to an improved method of lining furnaces.

Specifically it refers to an improved method of repairing the refractory lining for an electric furnace.

The chief difficulty experienced in maintaining intact a refractory lining in an electric furnace containing metal having a high melting point is due to the erosive effect of the molten metal as it washes over the surface of the furnace.

The method I have discovered consists in first. mixing a solution of sodium silicate in water with an equal weight of finely ground fireclay. Then thoroughly mixing the dilute solution of sodium silicate with the powdered fire clay, then heating the surface to which the fire clay is to be applied to a temperature of from 300 to 500 F., then applying with abrush the mixture of fire clay and sodium silicate solution in water to the heated surface. The coating thereby applied is only a few thousands of an inch in thickness.

Immediately after the first thin coating of fire clay and soluble silicate has been applied the flames of a blow torch is directed against the freshly painted surface so as to fix or bake the coatand also to raise the temperature of the surface to the temperature that it was before it was cooled by the application of the dilute sodium silicate solution.

Another coating of fire clay is applied as before and the heating operation is repeated until the surface of the furnace has been repaired or until the lining of the furnace is of the desired thickness.

An air brush may be substituted for the brush without departing from the scope of this invention.

This same method may be applied for 50 repairing the surface of containers for molten metal such as bullv ladies and the like.

This method may be used either in .con-

junction with fire bricks'or the lining may be used alone by building up any desired 55 thickness. i

' Serial No. 629,517.

The particular characteristic of this lining which .renders it permanent is that it does not flake off when subjected to high temperatures and it is. particularly adherent to a cast iron surface.

This application is a continuation of my co-pendingapp-lication filed August 11, 1922, Serial No. 581,239.

The maximum temperature referred to in this specification of 500 F. has been found to be essential when applying the first coating but when applying subsequent coatings this maximum temperature may be somewhat exceeded, although there is no advantage in raising the temperature above that temperature at which an adherent coating is given.

What I claim is:

1. The method of protecting and repairing the refactory lining of a furnace which consists in first heating the refactory surface of the furnace to between 300 and 500 IR, then painting the heated surface of the furnace with a wash containing not over 10% of soluble silicate in solution and a considerable quantity of. powdered fire clay in suspension, then heating. the surface of the furnace, then applyin another thin coat of fire clay with the solu le silicate binder, again heating the surface of the furnace and repeating the operation until the desired thickness of fire clay is applied to the surface of the furnace.

2. The method of protecting and repairing the refractory surface of'a furnace whichvconsists in first mixing a refractory insulating powder with Water containing a little heat-resisting binder in solution, then heating the refractory surface of the furnace to between 300 and 500 F., then painting the heated surface of the furnace with the said refractory insulating wash, then heating the furnace, then applying another thin coating of the refractory insulating Wash, again heating the surface of the furnace and repeating until a protective lining of sufficient thickness is obtained.

3. The method of protecting a refractory surface which consists infirst mixing a refractory insulating powder in Water con taining a little heat-resistin binder in solution, then heating the re ractory surface above the boiling point of water, then painting the heated refractory surface with said re ractory insulating wash whereby-a no thin adherent refractory insulating coating is applied.

4. The method of repairing the refractory lining of a, furnace which consists in first forming a dilute solution of soluble silicate in water, then mixing with the solution a considerable quantity of powdered fire clay, then applying the liquid Wash to the sur face to be repaired, and evaporating the water with heat in order to bond the particles of powdered fire clay together.

5. The method of repairing the refractory lining of a furnace which consists in first forming a. dilute solution of-solnble silicate in water, then mixing with the solution a considerable quantity of a powdered refractory, then applying the liquid wash to the surface to be repaired.

In testimony whereof I affix my signeture DANIEL H. MELOCHE. 

